Retaining wall block



FIG. 1 is a right side perspective view of a retaining wall block showing my new design;

FIG. 2 is a top plan view;

FIG. 3 is a right side elevation view, the left side view being a mirror image thereof;

FIG. 4 is a front elevation view; and,

FIG. 5 is a rear elevation view. 

The ornamental design for a retaining wall block, as shown and described. 